Be specific about whether you want a deep cleansing or just a clarifying treatment. Deep cleansing means they'll get crap out of your pores you didn't know existed, you'll be really red afterwards, and likely will have some breakouts for a bit after that day as things continue to process out. At least, that's how it was when I went for one.
The others I got were far more gentle - I was getting married, so they did everything they could to minimize the appearance of what acne I had and frankly, my skin was fabulous for months after that. So that's the one I'd recommend. I'm also a big fan of anyplace that uses Dermalogica products.
